A biomechanical and physiological comparison of deep-water running styles PublicDeposited

Descriptions

Purpose: The purpose of this investigation was to identify a deep-water running (DWR)
style that most closely approximates terrestrial running. Methods: Twenty healthy male
and female intercollegiate (NCAA III) distance runners were videotaped from the right
sagittal view while running on a treadmill (TR) and in deep water at 55-60% of their TR
VO₂[subscript max] using each of four DWR styles: shod cross-country (SCC), barefoot cross-country
(BCC), shod high-knee (SHK), and barefoot high-knee (BHK). All biomechanical data
were digitized and analyzed using the Peak Motus® system. Physiological variables of
interest were oxygen consumption (V0₂), heart rate (HR), and rating of perceived
exertion (RPE). Biomechanical variables of interest were horizontal (X) and vertical (Y)
displacement of the knee and ankle, and stride rate (SR). An ANOVA with repeated
measures was utilized to ascertain the differences across styles. The alpha significance
level was set at .05, and a post hoc pairwise analysis was conducted with a Bonferonni
adjustment of the alpha level. Results: Omnibus significant differences were found for
all physiological variables: VO₂ (p<.025), HR (p<.042), RPE (p<.000). However, the post
hoc pairwise comparisons revealed that only TR vs. SHK V0₂ (p<.005), and the RPE
responses for treadmill vs. all DWR styles exhibited significant differences (p<.000-.002). Omnibus tests for biomechanical variables exhibited statistical significance. The
post hoc pairwise comparisons revealed significant differences in SR (p<.000) between
TR (1.25 ± .08 Hz) and all DWR styles and also between the CC and HK styles of DWR
(SCC: 0.78 ± .08 Hz, BCC: 0.81 ± .08 Hz, SHK: 1.13 ± .10 Hz, BHK: 1.14 ± .10 Hz).
The CC style of DWR was found to be similar to TR with respect to linear ankle
displacement, whereas the HK style was significantly different from TR in all but two of
the 16 comparisons made for ankle and knee displacement. Conclusion: The CC style of
DWR is recommended as an adjunct to distance running training if the goal is to mimic
the ankle linear horizontal displacement of land-based running. However, if the goal is to
mimic SR, the HK style is a closer approximation than the CC style.